RightPSI

Fuel efficiency is reduced 1% for every 2.96 psi that its tires are below placard.
A 2005 Carnegie Mellon’s Steinbrenner Institute study finds that the average US driver would save $432 a year in gas savings (at $3 gallon of gas) if they filled their tires to placard.
In 1995 US Department of Energy said that under inflated tires wasted 4 million gallons of gasoline daily, or nearly 1.5 billion gallons annually.
NHTSA estimates that if all light vehicles meet the four-tire, 25% compliance option, average tread life will increase by 1,143 miles or an average value savings of $5.09

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